Internal-combustion rock-drill.



L. L. s00TT. INTERNAL COMBUSTION ROCK DRILL.

APPLICATION FILED NOV. 2, 1908.

- Patented NOV. 30, 19409.

UNITED sTATEs PATENT oEEioE.

LEWIS L. sooTT, oF `Jo1 LIN, Mrssouu.

To all whom it may concern:

Be it known that I, LEWIS L. SCOTT, a c1t1- z'en of the United States,residing at Joplin,-

in the county of Jasper and State of Missouri, have invented a new andImproved Internal-Combustion Rock-Drill, of which the following is aspecification.

This invention relates to improvements in linternal combustion rockdrilling machines or engines, intended for use in minesand quarries forthe drilling of holes to receive explosive charges for displacing orbreaking' away the rock or mineral.

The objects of this invention are: to produce a gas actuated rock drillwhich shall be of comparatively small dimensions, of compact, simple andinexpensive construction, having all moving parts entirely inclosed andthereby protected from damage consequent upon the rough handling suchmachines usually receive at the hands of their operators.

A further object is to provide an engine `in which the piston ispractically free (moved upward and downward entirely by the action ofthe internal fired gases upon it), yet connected to a crank shaft,(through a connecting rod which is slidingly and yieldingly connected tosame,) said: shaft being for the purpose of limiting the stroke of saidpiston, and being a means of manually starting said engine.

To these ends my invention consists in various features of constructionand arrangement of paris, as hereinafter described, illustrated in, theaccompanying drawings and particularly pointed out in the appendedclaims.

Referring to the accompanying drawings which form a part of thisspecification, Figurel 1. is a horizontalA plan view, (shown partly insection), of my improved internal combustion rock drill. Fig. 2. is a.vertical longitudinal section of same. Fig. 3 is a front end view'of Fig. 2, with head 2l removed. Fig. 4 is a section on the line X. X. ofFig. 2. Fig. 5 is a sectional View of a generator valve, (commonly usedon two This valve forms no part of the invention, but is shown for a.

purpose that will be seen later. Fig. 6 is an enlarged sectionalfview ofthe piston l0, on the line Y. Y. of Fig. 2. Fig. 7 is a side View of thebumping piece 4T.v Fig. 8 is an end view of seme.

Specification o'f Letters Patent.

Application led November 2,' 1908.

INTERNAL-coiviBUsTIoN Rock-DRILL.

4 Patented Nov. 30, 1909.

Serial No. 460,732.

-Like partsare represented by similar numerals of reference in theseveral views.

The numeral l denotes, what I term as the lirst or up er cylinder. rfheexplosive chamber 4G of t ie cylinder l is closed by the head l2; thechamber 2, (which receives the explosive mixture, drawn in at Vtheconnection 4, through a valve such as shownj in Fig. 5)

is closed by the crank case 3; the said crank case 3 carries the mainjournals 44 of the crank shaft; the balance wheels 1l join the mainshafts 44 through the crank pin 45. The piston l0, (which is attached orconnected to the piston 33 through the rod 36), is provided with thegrooves 19; the` piston pin 8, (which is connected to the crank pin 45through the rod 5), has ends, (made in square section), that projectbeyond the bearing surface ofl saidf pin in the rod 5, these ends areadapted to work or slide in the grooves .19 of the piston l0; thesliding movement of the pin 8 is limited,- and is stopped on one ,side bthe piece 47, (which bears against the said projectionsof pin 8, saidpiece 47 carries "the spring 42 which bears against the inner front wallof the piston' 10), and on the other side by the tool steel pieces 18,which are placed in the slots 22 of the piston 10 (refer to Fig. 6).vrlhe long ways 39 form a part of the casting l and vserve as slides,(which can be mounted on the shell and tripod commonly used on rockdrills), and also forms a guide for the cylinder' 13 which is secured tothe ways 39 by the screws 4l; the second or lower cylinder 13 is alsosecured to cylinder l by the bolts 48. The head l2 serves the purpose ofclosing the explosion chambers 15,`and 46, and also forms a journal forthe rod 3G and carries the packing rings 34, which fit around the rod36, to prevent the escape or leakage of gas from o-ne explosive chamberto the other; thc head l2 is clamped and held firm between the cylindersl and 1?, by the bolts 47 which are secured to the said cylinders. Thecylinders l and 13, and connected parts, are adjustable by the screw 37,or by some other equivalent or convenient device, in connection withwhich the usual shell and tripod support may be utilized.

The explosive chamber 15 of the cylinder 13 is closed by the head l2;the chamber-20, (which Ireceives the explosive charge, through a valvesuch as shown in Fig. 5, at the opening 4), is closed by the head 21;the said head 21 carries the chuck 30, which is adapted to rotate in thehead 21. The cylinder 13 is enlarged at its outer end to make room forthe enlarged portion of the rotating piece 35. The said rotating piece35 is rotatively mounted in the enlarged portion of the cylinder 13, andhas a small elongated projection, on the perimeter' of which are cut thespiral grooves 29; the rotating piece 35 has a small central. bore el?)through the elongated projection of the rotating piece 3o; in this borethe shank of the -drill steel 17 projects for a short distance; thehammer piece 23 of the piston 33 tits snugly in the said bore 43 and isadapted to reciprocate in the said bore and strike the shank of thedrill steell 1i' on each .downwarld'stroke of the pistons. The piston 33carries the pins 32, (and .is rigidly attached thereto), which areadapted to work in the spiral grooves 29, of the rotating piece 35, and.in the straight grooves 27 of the cylinder 13,' The rotating piece 35carries the 'pawls 2%, The chuck 30 has an enlarged diameter at itsinner end, and on the circumference of this enlarged diameter are cutthe common ratchet teeth d0. The pawls 24 are adapted to work in thesaid ratchet teeth, and are held in engagement with same by the springs25. rlhe drill. steel 17 may be provided with. the lugs 26, which tit inthe grooves 28 of the chuck o0, so that if the chuck .is rotated thedrill steel will be compelled to rotate in unison with it.- As thepiston 33, (and all rigidly connected parts), moves upward the pins 32(which travel in a straight line with the said piston and also work inthe straight grooves 27 of the cylinder 13), working in the spiralgrooves 2) of the rotating' piece 35, will cause the latter to rotate asmall amount; the rotation is transmitted troni the rotating piece 35,to the drill steel 17, through the pawls 2st, which engage the ratchetteeth 40 ot' the chuck 30; Athe said chuck 30- causing the drillsteel-to rotate with it as before described; on the down stroke of thepiston the pawls 2li run away from the ratchet teeth as will be fullyunderstood.

Any suitable sparking mechanism, commonly used on gasolene engines), maybe utilized to explode the charges after they have been introduced intothe explosive chanibcrs. l do not wishto be restricted to anyparticularkind.

rlhe operation of my improved internal combustion rock drill is asfollows: Assuming that an explosive charge has been drawn into thechamber 2, (on the downwmd movement ci the pistons, at opening itthrough a valve such as shown in Fig. 5), as the Ypistons move backwarda similar charge will be drawn into chamber 20, (at Il through a valvesuch as shown in Fig. o), while at the allinea,

same time the charge in chamber 2 is being compressed; when the pistonsapproach the end of the backwardfstroke the charge in chamber 2 willrush' through the passage 9 into the explosive chamber 46 of thecylinder1; as the pistons move forward the charges in chambers 4G andy 2Owilli-,be compressed, while at the same time a new charge will bedrawn-into the chamber 2; as the pistons apn preach the end of thedownward stroke the charge in chamber 20 rushes into the explosivechamber 15 et the cylinder 13, (through the passage 9), at this time thecharge in chamber 46 is err loded, (by means of a spark commonly used ongasolene engines), and the pistons will be driven backward under thepressure of the explosion in chamber' 1G; as the pistons move backward anew charge is drawn into chamber 20 and the charges in chambers 2 and 15are compressed; as the pistons reach the terminus of the upward strokethe burned gases are exhausted from chamber 46 through the port 7',while at the same time `the charge in chamber 2 rushes in'to chamber a6,and the charge in chamber 15 is exploded, (by a spark commonly used ongasolcnc engines), and drives the pistons downward. As these voperationscontinue it will be plainly' seen that an explosion will occur inchamber 46 on every upstroke, and a similar explosion will occur inchamber-,15 on every ldown stroke; further, that as the pistons movedownward, (by reason of the explosion in chamber 15), the piston pin S,(which is connected to the crank pin 45 through the rod 5), will slidebackward until it bears against the pieces 18, and will then be pulledforward with the-piston. i llhen the pistons approach the end of thedownward stroke, the projection Q8 of the piston 33 will strike theshank of the drill steel 17,- and said drill steel being in contact withthe rock tace, will penetrate same. Should the projection 23 strike thesaid shank bctore the crank pin 4:5 reaches the dead center line, thepistons will come to a stop, but the crank will continue around movingthe piston pin S'forward in the slides 19 ot' the piston 10. 1When, thecrank pin 45 reaches the dead center lineian explosion occurs inchan'iber 4G (as before described) and drives the pistons backward; onthe backward stroke the pin 8 will slide forward and bump against thespring 12, through the piece d?. lt will be plainly seen that the resultot this action is that of a free piston; the pistons heilig movedentirely by the pressure of the exploded charges, and not by energystored in lly wheels. vThe crank shattscrves the purpose ot' limitingthe stroke ot the pistons, (to insure the proper port opening, and toprevent an over stroke), without receiving any jar from the impacts ofthe pistons. aid crank is also a means of manually imparting motion tothe said pistons, for the purpose of starting the said engine.

The rotation ofthe drill steel occurs as before described,

Various changes in details of construction of component parts of themachine may be made without departing from the principle and intendedscope of the invention.

Having fully described my invention,what I claim as new and desire tosecure by Letters Patent isze 1. In an internal combustion rock drillingengine, a pair of spaced cylinders, a guide head connecting saidcylinders, a piston slidable Within the interior of each cylinder anddividing the same into mixing and explosion chambers' said explosionchambers being located proximal to said guide head; a piston rodslidable within said guide head and connected at opposite ends to saidpistons; a crank shaft, a connecting rod connected to said crank shaft,and yieldingly connected to the adjacent piston, and a rock cuttingdrill bit arranged. in striking relation to the other piston.

2. In an internal combustion rock drilling engine, a pair of s acedcylinders, a guide head connecting sai cylinders, a piston slidablewithin the interior of each cylinder and dividing the same into mixingand explosion chambers, said explosion chambers being located proximaltosaid guide head; a piston rod slidable within said guide head andconnected at opposite ends to said pistons; a crank shaft, a connectingrod connected to said crank shaft and yieldingly connected to theadjacent piston, for independent nievement with respect thereto, and arock cutting drill bit arranged inl striking relation to the otherpiston.

3. ln an internal combustion rock drilling engine, a pair of s acedcylinders, a guide head connecting said) cylinders, a piston slidablewithin the interior of each cylinder and dividing the same into mixingand explosion chambers, the explosion chambers being located proximal tosaid guide l1ead; a piston rod Islidable within said guide head andconnected at opposite ends to said pistons; a crank shaft, a connectingrod connecting said crank shaft and connected to said connecting rod,and upper piston; cushioning devices carried by the upper piston and arock cutting drill bit arranged in striking relation to the otherpiston.

l. A motor drill comprising a pair of opposed explosive engines arrangedin alinement with cach other and having their pistons nmtuallyconnected, the upper piston heilig formed with a socket and with longiiy i l tudinal slots communicating therewith; crank shaft, a connectingrod, connected 'te said shaft, formed with an eye at its lower end, atransversel disposed pin carried in ce the eye of said ro having itsends arranged for sliding movement in said longitudinal. slots, wherebyan inde endent movement of said shaft is permitte means for limitingsuch movement in beth directions and a rock cutting drill bit arrangedin striking rela" tion to the lower piston. A

5. A motor drill comprising a pair of opposed explosive engines arrangedin aiine ment with each other and having their pis tons mutuallyconnected, the interior of tlo cylinder of each engine being dividedinte mixing and an explosion chamber, the enpio sion chambers of theengines confronting each other; the upper piston being form with asocket and with longitudinal f communicating therewith; a crank siconnecting rod connected to said formed with an eye at its lower end, aVersely disposed pin carried in the eye saidrod having its ends arrangedfor s ing movement in said longitudinal slet whereby an independentmovement of si shaft is permitted; yielding means for li ing suchmovement in one direction, a means for limiting such movement in t.posite direction, and a rock cutting drill arranged in striking relationto the lower piston. l

6. A motor drill comprising apair of op" posed explosive enginesarranged in verticai alinement with each other and having their pistonsmutually connected, the upper pis being formed with a socket and withlongitudinal slots communicating therewith, if crank shaft, aconnecting.; rod, connected te said shaft, and formed with an eye at itslower end, a transversely disposed pin carried in the eye of said rodhaving its ends arranged for sliding movement in said` sie* wherebyindependent inoven'ient of seid crank shaft with respect to said pistonsis permitted; yieldin means interposed tween the inner wa l of saidsocket and sa?? pin for limiting the sliding movementJ of latter in onedirection and means located jacent the outer end of said socket for ii'ing such movement in the opposite dirci and a rock cutting drill bitarranged in sti ing relation to the lower )iston.

ln testimony whereof i have hereunto my hand thisI 29th day of Octoberd,

LEWIS L. SCtlT.

ilo

Witnesses ELLnN M. li/tnnriir, T. .l'. "Wenns

